Pump.



Patented Sept. II, 1900.

F. EDWARDS.

P U M P (Application filed Apr. 7, 1900.)

6 Sheets-:Sheet 1.

(No Model.)

imm,

6 Sheets-Sheet 2.

Patented Sept. ll, I900.

F. EDWARDS.

P U M P.

(Application filed Apr.

(No Model.)

Patented Sept. ll, I900. F. EDWARDS.

PUMP.

(Application filed Apr. 17, 1900.)

6 snemshaat a.

(No Model.)

(No Model.)

Patented 'Sept. II, I900. F. EDWARDS.

PUMP.

(Application filed Apr. 17, 1900.)

6 Sh ats$henf 4.

Patented Sept. ll,'l900.

F. EDWARDS.

P U NI P (Application filed Apr. 17, 1900.

6 Sheets-Sheet 5'.

(No Model.)

(No Model.)

Patented Sept. ll, I900.v F. EDWARDS.

PUMP.

(Application filed Apr. 17, p.900.) 6 Sheets-Sheet 6.

m: Noam; PETEYIS ca, mo'rouwo, wAsumamN, n1;

UNlTED STATES PATENT OFFICE.

FREDERICK EDWARDS, OF LONDON, ENGLAND.

PUMP.

$PEC1F1CAT1ON termin' part of Letters Patent No. 657,864, dated September 11, 1900.

Application filed April 17, 1900. berial No. 13,222. (No model.)

To aZZ whom it may concern:

Be it known that I, FREDERICK EDWARDS, a subject of the Queen of Great Britain and Ireland, residing at Bishopsgate street within, London, England, have invented Improvements in Pumps, of which the following is a specification.

This invention has reference to improvements in pumps, and more particularly to those of the kind specified in my former Letters Patent, No. 584,306, dated June 8, 1897, an object being to increase the etfectiveness of such pumps without the occurrence of shock or concussion.

Referring to the accompanying illustrative drawings, Figure 1 is an elevation of an airpump according to this invention. Fig. 2 is a vertical sectional view showing the construction illustrated in Fig. 3 in connection with the pump-cylinder and its relative relation thereto; Fig. 3, a longitudinal section illustrating an apparatus for controlling the admission of air to the air-pump barrel for cushioning purposes, and Fig. 4 a plan of said apparatus. Fig. 5 shows in longitudinal vertical section a modified arrangement? for controlling the admission of air to the pumpbarrel for cushioning purposes. Figs. 6 and 7 show sectional elevations, at right angles to each other, of another modification of apparatus for controlling the admission of air; and Fig. 8 is a sectional view of a further modification of such apparatus.

The pump illustrated is a steam-engine airpump of the kind referred to in the specification of my before-mentioned patent. It comprises a barrel a, formed with valveless inlet ports or openings 17, a valveless bucket 0, adapted to serve as a piston-valve, and a chamber cl, that is in communication with the condenser and whence the descent of the bucket displaces the water and causes it to pass through the inlet-openings into the barrel above the bucket, as well understood.

To enable the pump to work satisfactorily at high speeds without shock or concussion, in place of the ordinary snifting-valve I provide a fitting or apparatus f, whereby air is only admitted to the barrel while the bucket is making a discharge-stroke, so that the efficiency of the pump is not reduced by the admission of the air necessary for cushioning purposes, because such air is not admitted to it until it has drawn all it can from the con denser and communication therewith has been closed.

The construction of the apparatus f shown in Fig. l is illustrated to a larger scale in Figs. 3 and 4, wherein 1 is a passage which forms a communication between the atmos phere and the upper part of the pump-barrel, immediately under the delivery-valve. The wall of the passage 1 is formed with a valveseat 1, on which works aslide-valve 2, that travels in guides 3 and is actuated by means of a piston 4, arranged in a cylinder 5 in the back of the slide-valve 2. The piston 4 has a rod or spindle 6, that works through a stuffing-box 7 and is coupled to the rocking lever g by a link h, as shown in Fig. l. The cylinder has ports 8 leading to the working face of the slide-valve 2, and corresponding ports 9 lead from the valve-seat 1 to the passage 1. The cylinder has other ports 10, which lead to the atmosphere and are so arranged that when air is required to flow through the ports 8 it can easily pass to them from the atmosphere through the ports 10 and the cylinder 5. The cylinder 5 is closed at its respective ends by the stuffingbox 7 and plug 11, so as to enable the piston 4 to drive the cylinder and slidevalve by means of the air confined in the end portions of the cylinder, which are similar to moving dash-pots. Holes 12 permit the piston to move to the required extent before actuating the valve. 13 is a spring, which by means of an adjusting-screw l4 presses the slidevalve 2 against the seat 1 with more or less pressure, a saddle 15 being interposed between the spring and the back of the slidevalve. The piston 4 and cylinder 5 are so constructed and arranged that the piston must travel a certain distance in the cylinder before it can move it, and in moving this distance either opens or closes the ports 8. Dur-' motion. Then as the ports 8 pass the ports 9 no air will be admitted through them to the passage 1, owing to the port 8 being covered by the piston. During the discharge-stroke the cylinder 5 and sets the slide-valve 2 in motion, so that the ports 8 have to pass over and beyond the ports 9. Consequently as the ports 8 pass the ports 9 in an upward direction there will be free communication be-; tween the atmosphere and the pump-barrel for a given period, and air will, if the pressure in the pump-barrel be below that of the atmosphere, pass through the ports 10, 8, and 9 and the passage 1 into the pump-barrel, where, acting as a cushion between the pumpbucket and the cover of the barrel and its discharge-valves, it will, as is well known, tend to prevent concussion. The air thus admitted will be driven through the discharge valves with the water, and as the pump-bucket makes a return suction-stroke the piston 4 will also make a return stroke in the cylinder 5 and will close the ports 8 before they come opposite the ports 9 as the valve 2 is moved downwardly, as previously described. Thus no air is allowed to enter the pump-barrel during the suction-strokesthat is to say, while a vacuum is being formed in the barrel or while it is in communication with the condenser, the pressure in which can therefore be reduced below pressures obtainable by means of pumps fitted with snifting-valves in the ordinary manner. The effect of the air-cushions between the piston 4 and the valve-cylinder ends may be varied by more or less closing. cocks or valves (not shown) fitted thereto. The passage 1 may in some cases be provided with a non-return or snifting valve 16, the lift of which can be varied by means of a screw-spindle 17, the said valve serving to prevent the escape of the cushioning air or water as the pumpbucket nears the end of its discharge-stroke, so that it to some extent obviates very accurate fitting and adjustment of the controllingvalve 2 and its appurtenances.

Instead of the arrangement hereinbefore described other mechanical arrangements may be employedfor instance, tappets and contacts actuating air-admission valves or any other device which will cause air to be admitted on the one stroke and not on the other. Also the force imparted to the water during the descent of the bucket, as described in the specification of my before-mentioned patent, may be made use of to effect the same purpose.

Referring now to Fig. 5, 20 is a valve controlling the passage 1 and normally kept closed by a spring 21.. The valve is arranged to be lifted from its seat, so as to admit air to the pump-barrel on the discharge-stroke of the pump-bucket, by suitably-driven tappetgear. In the example the valve can move to a limited extent lengthwise of its spindle 23, which is provided at its lower end with a collar 24, held within a stirrup-piece 25, formed in one with the valve. To the spindle 23 is pivoted a rod or link 26, formed at its free end with a catch or tooth 27, kept by a spring 28 in the path of a projection 29 on a rod 30, that is attached to the pump cross-head or is otherwise driven. As the bucket makes its suction-stroke the rod 30 descends with it, and the projection 29, pressing to one side the link 26, rides over the tooth 27, the valve during this stroke being held closed by its spring 21,

' which is sufficiently strong for this purpose.

During the discharge-stroke of the pumpbucket the rod 30 rises, its projection 29 em gaging with the tooth 27 and then lifting the valve 20 in opposition to the spring 21, so as to allow air to enter the pump-barrel through the passage 1. 26 is a fixed roller against which the link 26 is caused to bear by its spring 28 and which upon the continued upward movement forces the tooth 27 out of engagement with the projection 29, whereupon the spring 21 closes the valve 20 and restores the parts to the positions shown.

The passage 1 in the example illustrated in Figs. 6 and 7 is controlled by a piston-valve 20, working in a cylindrical chamber 32, that is formed with ports 32 and 32 ,communicating, respectively, with those portions of the passage 1 which lead to the pump and to the atmosphere. The lower end of the chamber 32 opens into a chamber 33, which is in communication with the chamberdaround the pumpbarrel, through the inclined pipe 34, the upper portion of the lower end of which extends into said chamber, as shown, and forms a guide for causing water to enter the pipe. Within the chamber 33 is a piston or valve 35, carried by the rod 36 of the piston-val ve 20 and arranged immediately above the end of the pipe 34. The chamber 32 also communicates through a passage 37 with the pump-barrel at about the same level as the passage 1. The spindle 36 extends through adjustable guides 38, and its motion is limited by stops 39, which come in contact with buffers carried by the guides. The spindle and attached parts are counterbalanced by a weighted lever 40, connected to the spindle by a link 44, and the movement of the spindle is retarded by an adjustable spring-brake 45. The action of the apparatus is as follows: When the pump-bucket displaces water from the chamber d, some is driven up the pipe 34., so that it strikes the piston or valve 35 and forces up the piston-valve 20, which places the ports 32 and 32 in communication, so that air can pass through the passage 1 to the barrel. When the pressure in the barrel has been raised in this way or by the ascent of the bucket, the pressure in the passage 37, above the piston-valve 20, becomes greater than that in the chamber 33 and drives down the valve 20, which cuts off communication between the barrel and the atmosphere before the next suction-stroke commences. The apparatus is designed to open communication .between the barrel and the atmosphere after the pump-bucket has commenced each discharge-stroke, and as the movement of the valve is dependent upon the water displaced from the chamber d by the pump-bucket, such communication cannot under any circumstances be opened until the bucket has practically completed its suction-stroke and opened the ports in the pump-barrel. If it be required to further delay the admission of air to the barrel, the inlet to the passage 1 may be formed with a funnel-shaped receiver 46, to which water is admitted during the working of the pump, which water must be blown through the passage 1 into the barrel before air can enter, thus giving the bucket time to again close the ports before the air is admitted.

Fig. 8 illustrates a further modification. In this case the passage 1 is controlled by a valve 20, similar to a snifting-valve, but formed With a stirrup-piece 20, which em-' braces a spring-lever 20 fulcrumed at 20. One end of the lever is attached to a tensionspring 20, which tends to open the valve, and the other end rests upon a cam 20", carried by a shaft 20 that may conveniently be driven by chain-gear or otherwise from the crank-shaft, if the pump be crank-driven. The concentric portion of the cam forces the lever against an adjustable screw 20 carried by the stirrup-piece 20, so that the valve cannot lift, and the cam-shaft is so geared as to revolve at the same speed as the crankshaft, and the cam is so set that its recessed portion comes under the lever, so as to relieve the pressure on the screw 20 and to allow the valve to open only While the pumpbucket is making a discharge-stroke. The lever and cam are formed as shown, so that the cam may be revolved in either direction, and, if desired, the lever may be provided with an antifriction-roller.

\Vhat I claim is- 1. In a pump, the combination with the barrel having a main inlet and a bucket, of an air-inlet to said barrel, a valve controlling said inlet, and means whereby said valve is closed during its suction and is opened during the discharge stroke of the bucket, substantially as set forth.

2. In a pump, the combination with a barrel having main inlet-openings, a bucket adapted to control said main inlet-opening, an air-inlet to said barrel, a valve controlling said air-inlet, and means whereby said valve is kept closed during the suction-stroke until said main inlet-opening in the barrel communicates with the discharge side of the bucket, substantially as set forth.

3. In a pump, the combination of a barrel having a main inlet, a bucket, means for reciprocating the said bucket,an air-inlet to said barrel, a valve controlling said inlet, a lever for holding the valve closed during the suc- .tion-stroke, and means for actuating said lever to permit the opening of the valve during the discharge-stroke of the bucket, substantially as set forth.

4:. In a pump, the combination of a barrel having a main inlet, a bucket, means for re ciprocating said bucket, an air-inlet to said barrel, a valve controlling said inlet, a lever connected to said valve, and a cam adapted to actuate said lever and close the valve during the suction-stroke and permit it to open during the discharge-stroke, substantially as set forth.

5. In a pump, the combination of a barrel having a main inlet, a bucket, means for reciprocating said bucket, an air-inlet to said barrel, a valve controlling said inlet, a lever connected to said valve, a spring connected to said lever and tending to open the valve, and a cam which bears against said lever and is adapted to keep said valve closed during the suction-stroke of the bucket, substantially as set forth.

6. In an air-pump, the combination with the barrel having a main inlet and a bucket, of an air-inlet to said barrel, means for opening the inlet during the discharge-stroke and adapted to close the said inlet during the suction-stroke of the bucket, said means also preventing outflow through said inlet, substantially as set forth.

7. In an air-pump, the combination with the barrel having a main inlet, and a bucket,

of an air-inlet to said barrel, a non-return valve adapted to control said inlet, means for opening said valve during the dischargestroke and for preventing said valve opening during the suction-stroke of the bucket, substantially as set forth.

Signed at 62 Bishopsgate street within, London, England, this 6th day of April, 1900. FREDERICK EDWARDS. Witnesses:

G. W. HOLE, ARTHUR .WoosNAM. 

